Providing the first theoretical analysis of regulation of public services for less developed countries (LDCs), Jean-Jacques Laffont demonstrates how the debate between price-cap regulation and cost of service regulation is affected by the characteristics of LDCs. Laffont develops a new theory of regulation with limited enforcement capabilities, and discusses the delicate issue of access pricing in view of LDCs' specificities. His evaluation of the different ways to organize the regulatory institutions makes a significant contribution to the field.